Oil Spill Modelling

In 2010 BP was responsible for the Deepwater Horizon well blowout resulting in a catastrophic oil spill in the Gulf of Mexico. Oil and gas spilled into the Gulf of Mexico for 87 days until the well could be successfully capped.

BP’s catastrophic Gulf of Mexico oil blowout and spill occurred during exploration drilling — the same activity now proposed in the Great Australian Bight. Early proposals regarding the Bight included deepwater drilling at the frontier of technical capacity; drilling at water depths of up to 2.2km, and up to 3km into the sea bed in extraordinarily rough, unpredictable and remote seas of the Bight.

It is now estimated that 4.9 million barrels of oil spilled from the well with a flow rate reaching 62,200 barrels per day in April 2010. Inaccurate flow rates were originally reported at an order of magnitude less than this — 1,000–6,000 barrels per day — raising concerns about oil companies’ capacity to accurately determine such factors during assessment processes.

A spill catastrophe of the scale seen in the Gulf of Mexico would be disastrous for the marine life of the Great Australian Bight and marine industries (particularly fishing and tourism) across southern Australia.

Given the lack of information provided to the public by BP during their consultation phase, independent expert oil spill modelling was commissioned to enable the community to understand and consider these risks. The results demonstrate the unacceptable scale of the risks presented by drilling in the Bight.

Conducted by oceanographer and oil spill modelling expert Laurent C. M. Lebreton, MSc., the modelling shows due to strong winds and highly energetic waves in the Southern Ocean, the trajectories of an oil slick and its particles have the potential to cover vast areas of Australia’s southern waters and coastline.

If a blowout and spill were to occur in summer, aside from the direct and severe impact in near water, the oil would very likely impact the shores of Western Australia. Simulations show oil contamination could reach as far as Albany and Denmark. Under these conditions, the model predicts that within four months, an area of roughly 213,000km2 would have an 80% chance of surface oil thickness likely to trigger the closure of fisheries.

If a blowout and spill were to occur in winter, the oil would very likely impact the Eyre Peninsula, Kangaroo Island, and Spencer Gulf in South Australia. Simulations show oil could impact much of the Victorian and Tasmanian coastline, right through the Bass Straight towards New Zealand as well. Under these conditions, the model predicts that within four months, an area of roughly 265,000km2 would have an 80% chance of surface oil thickness likely to trigger the closure of fisheries.

These potential impacts would devastate marine life, fisheries and coastal communities, and would seriously tarnish the clean, pristine image of Australia’s Southern Ocean and beaches. This is compounded by the fact that in the event of a well blowout — as uncovered by a Freedom of Information request from the Wilderness Society — BP would have had to bring critical response infrastructure from Singapore (more than 4,800km away) and/or Houston, Texas (more than 14,000km away) and that if a relief well was needed this could take 157 days to arrive.